support basic auth with just pass token (#4063)

* feat: support basic auth with token

* refactor: change param name

core/base-service/auth-helper.js

@@ -1,14 +1,26 @@
 'use strict'
 
 class AuthHelper {
-  constructor({ userKey, passKey, isRequired = false }, privateConfig) {
+  constructor(
+    {
+      userKey,
+      passKey,
+      isRequired = false,
+      defaultToEmptyStringForUser = false,
+    },
+    privateConfig
+  ) {
     if (!userKey && !passKey) {
       throw Error('Expected userKey or passKey to be set')
     }
 
     this._userKey = userKey
     this._passKey = passKey
-    this.user = userKey ? privateConfig[userKey] : undefined
+    if (userKey) {
+      this.user = privateConfig[userKey]
+    } else {
+      this.user = defaultToEmptyStringForUser ? '' : undefined
+    }
     this.pass = passKey ? privateConfig[passKey] : undefined
     this.isRequired = isRequired
   }

core/base-service/auth-helper.spec.js

@@ -91,6 +91,13 @@ describe('AuthHelper', function() {
       given({ userKey: 'myci_user', passKey: 'myci_pass' }, {}).expect(
         undefined
       )
+      given(
+        { passKey: 'myci_pass', defaultToEmptyStringForUser: true },
+        { myci_pass: 'abc123' }
+      ).expect({
+        user: '',
+        pass: 'abc123',
+      })
     })
   })
 })

services/azure-devops/azure-devops-base.js

@@ -16,7 +16,10 @@ const latestBuildSchema = Joi.object({
 
 module.exports = class AzureDevOpsBase extends BaseJsonService {
   static get auth() {
-    return { passKey: 'azure_devops_token' }
+    return {
+      passKey: 'azure_devops_token',
+      defaultToEmptyStringForUser: true,
+    }
   }
 
   async fetch({ url, options, schema, errorMessages }) {